Expression of CXC chemokine receptor 4 (CXCR4) and α-smooth muscle actin (α-SMA) in c-kit<sup>+</sup> cells.

<p>Representative optical sections obtained by confocal microscopy demonstrating the co-expression of CXCR4, α-SMA and c-kit in the pulmonary artery of a naïve animal and in pulmonary vascular lesion cells of animals with SU5416/chronic hypoxia (SuHx) induced severe PAH. The inserts show the area outlined by a box in more detail. Arrows indicate triple positive cells in the inserts. Nuclear counterstaining: 4′-6-diamidino-2-phenylindole (DAPI). Magnification: 400×. Scale bar: 20 µm.</p>